/* =============================================
   styles.css — FullGas Planificador Nutricional v2.8
   Mobile-first design
   ============================================= */

/* ── 1. Reset & Custom Properties ────────────── */

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  /* Brand colors */
  --fg-green: #a9d42d;
  --fg-green-hover: rgba(169, 212, 45, 0.76);
  --fg-green-soft: rgba(169, 212, 45, 0.10);
  --fg-green-dark: #8ab224;
  --fg-black: #191919;
  --fg-black-deep: #111111;
  --fg-white: #ffffff;

  /* Gray scale */
  --fg-gray-100: #f3f3f3;
  --fg-gray-200: #e8e8e8;
  --fg-gray-300: #d1d1d1;
  --fg-gray-500: #707070;
  --fg-gray-700: #3d3d3d;

  /* Semantic aliases */
  --color-primary: var(--fg-green);
  --color-primary-hover: var(--fg-green-hover);
  --color-primary-dark: var(--fg-green-dark);
  --color-bg: var(--fg-gray-100);
  --color-surface: var(--fg-white);
  --color-text: var(--fg-black);
  --color-text-secondary: var(--fg-gray-500);
  --color-text-on-dark: var(--fg-white);
  --color-border: var(--fg-gray-300);
  --color-error: #d32f2f;
  --color-error-bg: #fdecea;
  --color-warning: #e65100;
  --color-info-blue: #4A90D9;

  /* Spacing (8px grid) */
  --sp-1: 4px;
  --sp-2: 8px;
  --sp-3: 12px;
  --sp-4: 16px;
  --sp-5: 20px;
  --sp-6: 24px;
  --sp-8: 32px;
  --sp-10: 40px;
  --sp-12: 48px;

  /* Radii */
  --radius: 8px;
  --radius-sm: 6px;
  --radius-lg: 12px;

  /* Shadows */
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-sticky: 0 4px 16px rgba(0, 0, 0, 0.15);

  /* Transitions */
  --transition: 0.2s ease;
  --transition-slow: 0.3s ease;

  /* Typography */
  --font-ui: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'Space Mono', monospace;

  /* Layout */
  --header-height: 44px;
  --input-panel-width: 360px;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

/* ── 2. Base Typography ──────────────────────── */

body {
  font-family: var(--font-ui);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.5;
  min-height: 100vh;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4 {
  font-family: var(--font-mono);
  font-weight: 700;
  line-height: 1.2;
}

a {
  color: var(--fg-green);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* ── 3. Header ───────────────────────────────── */

.header {
  background: var(--fg-black);
  color: var(--color-text-on-dark);
  height: var(--header-height);
  position: sticky;
  top: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  padding: 0 var(--sp-4);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  width: 100%;
}

.header-logo {
  height: 22px;
  width: auto;
  flex-shrink: 0;
  filter: invert(1);
}

.header-title {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.header-accent {
  color: var(--fg-green);
}

/* ── 4. App Container ────────────────────────── */

.app-container {
  display: flex;
  flex-direction: column;
  min-height: calc(100vh - var(--header-height));
  max-width: 1200px;
  margin: 0 auto;
}

/* ── 5. Form Section ─────────────────────────── */

.form-section {
  padding: var(--sp-4);
  padding-bottom: 80px; /* Space for sticky button */
}

/* ── 6. Context Selector ─────────────────────── */

.context-selector {
  display: flex;
  background: var(--fg-gray-200);
  border-radius: var(--radius);
  padding: 3px;
  margin-bottom: var(--sp-4);
  width: 100%;
}

.ctx-btn {
  flex: 1;
  min-height: 48px;
  padding: var(--sp-2) var(--sp-3);
  border: none;
  background: transparent;
  color: var(--color-text-secondary);
  font-family: var(--font-ui);
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  border-radius: var(--radius-sm);
  transition: background var(--transition), color var(--transition), box-shadow var(--transition);
  text-align: center;
  -webkit-tap-highlight-color: transparent;
}

.ctx-btn:hover {
  color: var(--color-text);
}

.ctx-btn.active {
  background: var(--fg-green);
  color: var(--fg-gray-700);
  box-shadow: 0 2px 6px rgba(169, 212, 45, 0.3);
}

/* ── 7. Sub-type Selector ────────────────────── */

.subtype-group {
  margin-bottom: var(--sp-3);
}

.subtype-wrap {
  /* Container for each sub-type variant */
}

.subtype-pills {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.subtype-pills::-webkit-scrollbar {
  display: none;
}

.subtype-pills select {
  width: 100%;
  font-family: var(--font-ui);
  font-size: 16px; /* Prevents iOS zoom */
  font-weight: 500;
  padding: var(--sp-3) var(--sp-4);
  padding-right: var(--sp-10);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  color: var(--color-text);
  height: 44px;
  cursor: pointer;
  transition: border-color var(--transition);
  appearance: none;
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23707070' d='M6 8.825L1.175 4 2.238 2.938 6 6.7 9.763 2.937 10.825 4z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 12px;
}

.subtype-pills select:focus {
  outline: none;
  border-color: var(--fg-green);
  box-shadow: 0 0 0 3px rgba(169, 212, 45, 0.2);
}

/* ── 8. Input Cards ──────────────────────────── */

.input-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: var(--sp-4);
  margin-bottom: var(--sp-3);
}

/* ── 9. Form Fields ──────────────────────────── */

.form-field {
  margin-bottom: var(--sp-3);
}

.form-field:last-child {
  margin-bottom: 0;
}

.form-field label {
  display: block;
  font-family: var(--font-ui);
  font-size: 0.68rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  margin-bottom: var(--sp-1);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.form-field input[type="number"],
.form-field select {
  width: 100%;
  font-family: var(--font-ui);
  font-size: 16px; /* Prevents iOS zoom on focus */
  padding: var(--sp-3) var(--sp-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius);
  color: var(--color-text);
  background: var(--fg-white);
  height: 44px;
  transition: border-color var(--transition), box-shadow var(--transition);
  appearance: none;
  -webkit-appearance: none;
}

.form-field select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23707070' d='M6 8.825L1.175 4 2.238 2.938 6 6.7 9.763 2.937 10.825 4z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 12px;
  padding-right: var(--sp-10);
}

.form-field input[type="number"]:focus,
.form-field select:focus {
  outline: none;
  border-color: var(--fg-green);
  box-shadow: 0 0 0 3px rgba(169, 212, 45, 0.2);
}

.form-field input[type="number"] {
  -moz-appearance: textfield;
}

.form-field input[type="number"]::-webkit-inner-spin-button,
.form-field input[type="number"]::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

/* FTP + Peso side by side (always 2 columns) */
.input-row-2col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-3);
}

/* FTP note */
.ftp-note {
  display: block;
  font-family: var(--font-ui);
  font-size: 0.65rem;
  color: var(--color-text-secondary);
  margin-top: var(--sp-1);
  font-style: italic;
}

/* Duration row */
.duracion-row {
  display: flex;
  gap: var(--sp-3);
}

.duracion-input-wrap {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  flex: 1;
}

.duracion-input-wrap input {
  width: 100%;
  font-family: var(--font-ui);
  font-size: 16px; /* Prevents iOS zoom */
  padding: var(--sp-3) var(--sp-3);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius);
  color: var(--color-text);
  background: var(--fg-white);
  height: 44px;
  text-align: center;
  transition: border-color var(--transition), box-shadow var(--transition);
  -moz-appearance: textfield;
  -webkit-appearance: none;
}

.duracion-input-wrap input::-webkit-inner-spin-button,
.duracion-input-wrap input::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.duracion-input-wrap input:focus {
  outline: none;
  border-color: var(--fg-green);
  box-shadow: 0 0 0 3px rgba(169, 212, 45, 0.2);
}

.duracion-suffix {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  flex-shrink: 0;
  min-width: 24px;
}

/* ── 10. Toggle Switch ───────────────────────── */

.toggle-field {
  display: flex;
  flex-direction: column;
}

.toggle-row {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  min-height: 44px; /* Touch target */
}

.toggle-label-text {
  font-family: var(--font-ui);
  font-size: 0.82rem;
  color: var(--color-text-secondary);
}

.toggle-switch {
  position: relative;
  width: 48px;
  height: 26px;
  flex-shrink: 0;
  cursor: pointer;
}

.toggle-switch input {
  opacity: 0;
  width: 0;
  height: 0;
  position: absolute;
}

.toggle-slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: var(--fg-gray-300);
  border-radius: 26px;
  transition: background-color var(--transition);
}

.toggle-slider::before {
  content: '';
  position: absolute;
  height: 20px;
  width: 20px;
  left: 3px;
  bottom: 3px;
  background-color: var(--fg-white);
  border-radius: 50%;
  transition: transform var(--transition);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.15);
}

.toggle-switch input:checked + .toggle-slider {
  background-color: var(--fg-green);
}

.toggle-switch input:checked + .toggle-slider::before {
  transform: translateX(22px);
}

/* ── 11. Collapsible Cards (details/summary) ── */

.collapsible-card {
  /* Inherits .input-card styles */
}

.collapsible-summary {
  font-family: var(--font-ui);
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--color-text);
  cursor: pointer;
  padding: var(--sp-2) 0;
  border-left: 3px solid var(--fg-green);
  padding-left: var(--sp-3);
  margin-left: calc(-1 * var(--sp-4));
  padding-right: var(--sp-4);
  width: calc(100% + var(--sp-4));
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 44px; /* Touch target */
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}

.collapsible-summary::-webkit-details-marker {
  display: none;
}

.collapsible-summary::after {
  content: '';
  width: 8px;
  height: 8px;
  border-right: 2px solid var(--color-text-secondary);
  border-bottom: 2px solid var(--color-text-secondary);
  transform: rotate(45deg);
  transition: transform var(--transition);
  flex-shrink: 0;
  margin-right: var(--sp-2);
}

details[open] > .collapsible-summary::after {
  transform: rotate(-135deg);
}

.collapsible-content {
  padding-top: var(--sp-3);
}

/* ── 12. Semaforo Indicator ──────────────────── */

.semaforo-indicator {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  margin-top: var(--sp-2);
  font-size: 0.75rem;
  font-family: var(--font-ui);
  font-weight: 500;
  min-height: 20px;
}

.semaforo-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  flex-shrink: 0;
}

/* ── 13. Error Box ───────────────────────────── */

.error-box {
  display: none;
  background: var(--color-error-bg);
  border: 1px solid var(--color-error);
  border-radius: var(--radius);
  padding: var(--sp-3) var(--sp-4);
  margin-bottom: var(--sp-3);
  color: var(--color-error);
  font-size: 0.82rem;
  line-height: 1.5;
}

.error-box ul {
  list-style: disc inside;
  margin: 0;
  padding: 0;
}

.error-box li {
  margin-bottom: var(--sp-1);
}

.error-box li:last-child {
  margin-bottom: 0;
}

/* ── 14. Calculate Button ────────────────────── */

.btn-calcular-wrap {
  position: sticky;
  bottom: 0;
  left: 0;
  right: 0;
  padding: var(--sp-3) 0;
  background: linear-gradient(to top, var(--color-bg) 60%, transparent);
  z-index: 50;
  margin: 0 calc(-1 * var(--sp-4));
  padding-left: var(--sp-4);
  padding-right: var(--sp-4);
  padding-bottom: var(--sp-4);
}

.btn-calcular {
  display: block;
  width: 100%;
  height: 52px;
  padding: var(--sp-3) var(--sp-4);
  background: var(--fg-green);
  color: var(--fg-gray-700);
  font-family: var(--font-ui);
  font-size: 0.95rem;
  font-weight: 700;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  box-shadow: var(--shadow-md);
  -webkit-tap-highlight-color: transparent;
}

.btn-calcular:hover {
  background: var(--color-primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-lg);
}

.btn-calcular:active {
  transform: translateY(0);
  box-shadow: var(--shadow);
}

/* ── 15. Results Section ─────────────────────── */

.results-section {
  padding: var(--sp-4);
  animation: fadeIn 0.3s ease;
}

/* ── 16. Hero Metrics ────────────────────────── */

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-3);
  margin-bottom: var(--sp-4);
}

.metric {
  background: var(--fg-black);
  color: var(--color-text-on-dark);
  border-radius: var(--radius-lg);
  padding: var(--sp-4) var(--sp-3);
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-1);
  min-width: 0;
}

.metric-value {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--fg-green);
  line-height: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  word-break: break-all;
  max-width: 100%;
}

.metric-label {
  font-family: var(--font-ui);
  font-size: 0.62rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--fg-gray-300);
}

/* ── 17. Carry Card ──────────────────────────── */

.carry-card {
  background: linear-gradient(135deg, var(--fg-black) 0%, #2a2a2a 100%);
  color: var(--color-text-on-dark);
  border-radius: var(--radius-lg);
  padding: var(--sp-4);
  margin-bottom: var(--sp-3);
}

.carry-card h3 {
  font-family: var(--font-ui);
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--fg-green);
  margin-bottom: var(--sp-3);
}

.carry-grid {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
  align-items: center;
}

.carry-item {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  background: rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-sm);
  padding: var(--sp-2) var(--sp-3);
}

.carry-item .carry-icon {
  font-size: 1.3rem;
}

.carry-item .carry-qty {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--fg-green);
}

.carry-item .carry-label {
  font-family: var(--font-ui);
  font-size: 0.72rem;
  color: var(--fg-gray-300);
}

/* ── 18. Hydration Card ──────────────────────── */

.hydration-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: var(--sp-4);
  margin-bottom: var(--sp-3);
  border-left: 4px solid var(--color-info-blue);
}

.hydration-card h3 {
  font-family: var(--font-ui);
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--sp-3);
}

/* ── 19. Pack Tabs ───────────────────────────── */

.packs-section {
  margin-bottom: var(--sp-3);
}

.pack-tabs {
  display: flex;
  background: var(--fg-gray-200);
  border-radius: var(--radius-sm);
  padding: 2px;
  margin-bottom: var(--sp-3);
  width: 100%;
}

.pack-tab {
  flex: 1;
  font-family: var(--font-ui);
  padding: var(--sp-2) var(--sp-3);
  border: none;
  background: transparent;
  color: var(--color-text-secondary);
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  border-radius: var(--radius-sm);
  transition: background var(--transition), color var(--transition);
  text-align: center;
  min-height: 40px;
  -webkit-tap-highlight-color: transparent;
}

.pack-tab:hover {
  color: var(--color-text);
}

.pack-tab.active {
  background: var(--fg-green);
  color: var(--fg-gray-700);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

/* ── 20. Pack Content ────────────────────────── */

.pack-content {
  /* Container for dynamically rendered pack cards */
}

.pack-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: var(--sp-4);
  border-left: 4px solid var(--fg-green);
  animation: fadeIn 0.2s ease;
}

.pack-card.fuera-tolerancia {
  border-left-color: var(--color-warning);
}

.pack-card h4 {
  font-family: var(--font-ui);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--fg-black);
  margin-bottom: var(--sp-3);
}

.pack-item {
  padding: var(--sp-2) 0;
  font-size: 0.82rem;
  border-bottom: 1px solid var(--fg-gray-200);
  display: flex;
  align-items: flex-start;
  gap: var(--sp-2);
  flex-wrap: wrap;
}

.pack-item:last-of-type {
  border-bottom: none;
}

.pack-item .icono {
  font-size: 1.1rem;
  flex-shrink: 0;
}

.pack-item .unit-detail {
  font-size: 0.68rem;
  color: var(--color-text-secondary);
}

.pack-total {
  margin-top: var(--sp-3);
  padding-top: var(--sp-2);
  border-top: 2px solid var(--fg-green);
  font-size: 0.85rem;
}

.pack-total .warning {
  color: var(--color-warning);
  font-weight: 600;
  font-size: 0.75rem;
}

.pack-mensaje-orientativo {
  background: var(--fg-green-soft);
  border-left: 3px solid var(--fg-green);
  padding: var(--sp-3) var(--sp-4);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  color: var(--fg-gray-700);
  margin-top: var(--sp-3);
}

/* ── 21. Tech Details (Collapsible) ──────────── */

.tech-details {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: var(--sp-4);
  margin-bottom: var(--sp-3);
  color: var(--color-text-secondary);
  font-size: 0.82rem;
}

.tech-details .collapsible-summary {
  color: var(--color-text-secondary);
  font-size: 0.82rem;
  font-weight: 500;
}

.tech-details .collapsible-content {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--color-text-secondary);
}

.tech-details table {
  width: 100%;
  border-collapse: collapse;
  margin-top: var(--sp-2);
}

.tech-details th,
.tech-details td {
  text-align: left;
  padding: var(--sp-2) var(--sp-3);
  border-bottom: 1px solid var(--fg-gray-200);
  font-size: 0.78rem;
}

.tech-details th {
  font-weight: 600;
  color: var(--color-text);
}

/* ── 22. Export Section ──────────────────────── */

.export-section {
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  margin-bottom: var(--sp-4);
}

.btn-export {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  width: 100%;
  min-height: 48px;
  padding: var(--sp-3) var(--sp-4);
  background: var(--fg-black);
  color: var(--fg-green);
  font-family: var(--font-ui);
  font-size: 0.88rem;
  font-weight: 600;
  border: 2px solid var(--fg-green);
  border-radius: var(--radius);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
  -webkit-tap-highlight-color: transparent;
}

.btn-export:hover {
  background: var(--fg-green);
  color: var(--fg-gray-700);
}

.btn-export:active {
  background: var(--fg-green-dark);
  color: var(--fg-white);
}

.export-feedback {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--fg-green-dark);
  text-align: center;
  min-height: 20px;
  opacity: 0;
  transition: opacity var(--transition-slow);
}

.export-feedback.visible {
  opacity: 1;
}

/* ── 23. Edit Button ─────────────────────────── */

.btn-editar {
  display: block;
  width: 100%;
  min-height: 48px;
  padding: var(--sp-3) var(--sp-4);
  background: transparent;
  color: var(--fg-green);
  font-family: var(--font-ui);
  font-size: 0.88rem;
  font-weight: 600;
  border: 2px solid var(--fg-green);
  border-radius: var(--radius);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
  -webkit-tap-highlight-color: transparent;
}

.btn-editar:hover {
  background: var(--fg-green-soft);
}

.btn-editar:active {
  background: var(--fg-green);
  color: var(--fg-gray-700);
}

/* ── 24. Product Links ───────────────────────── */

.product-link {
  color: var(--fg-black);
  font-weight: 600;
  text-decoration: none;
  border-bottom: 1.5px solid var(--fg-green);
  transition: border-color var(--transition), color var(--transition);
}

.product-link:hover {
  color: var(--fg-green-dark);
  border-bottom-color: var(--fg-green-dark);
  text-decoration: none;
}

/* ── 25. Variante Cards (product images) ─────── */

.variantes {
  margin-top: var(--sp-1);
  font-size: 0.7rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
  width: 100%;
}

.variantes-grid {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
  margin-top: var(--sp-1);
  width: 100%;
}

.variante-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-decoration: none;
  background: var(--fg-green-soft);
  border-radius: var(--radius-sm);
  padding: var(--sp-1);
  width: 68px;
  transition: background var(--transition), transform 0.15s ease;
}

.variante-card:hover {
  background: var(--fg-green);
  transform: translateY(-2px);
  text-decoration: none;
}

.variante-img {
  width: 48px;
  height: 48px;
  object-fit: contain;
  border-radius: 4px;
  margin-bottom: var(--sp-1);
}

.variante-nombre {
  font-size: 0.55rem;
  color: var(--fg-gray-700);
  text-align: center;
  line-height: 1.2;
  word-break: break-word;
}

/* ── 26. Footer ──────────────────────────────── */

.footer {
  background: var(--fg-black);
  text-align: center;
  padding: var(--sp-6) var(--sp-4);
  color: var(--fg-gray-500);
  font-family: var(--font-ui);
  font-size: 0.72rem;
}

.footer a {
  color: var(--fg-green);
  text-decoration: none;
}

.footer a:hover {
  text-decoration: underline;
}

.footer-logo {
  height: 20px;
  filter: invert(1);
  opacity: 0.5;
  margin-bottom: var(--sp-2);
  display: block;
  margin-left: auto;
  margin-right: auto;
}

.footer p {
  margin-top: var(--sp-1);
}

/* ── 27. Animations ──────────────────────────── */

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInScale {
  from {
    opacity: 0;
    transform: scale(0.95);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

/* ── 28. Hydration Lines & Warnings ──────────── */

.hydration-line {
  font-size: 0.82rem;
  line-height: 1.6;
  margin-bottom: var(--sp-2);
  color: var(--color-text);
}

.hydration-line:last-child {
  margin-bottom: 0;
}

.hydration-warnings {
  margin-top: var(--sp-3);
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
}

.hydration-warning {
  background: #FFF3E0;
  border-left: 3px solid var(--color-warning);
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--radius-sm);
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--color-warning);
}

.hydration-warning-danger {
  background: #FFEBEE;
  border-left-color: var(--color-error);
  color: var(--color-error);
}

.hydration-warning-info {
  background: #E3F2FD;
  border-left-color: var(--color-info-blue);
  color: #1565C0;
}

/* ── 29. Pack Detail (app.js classes) ────────── */

.pack-detail {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: var(--sp-4);
  border-left: 4px solid var(--fg-green);
  animation: fadeIn 0.2s ease;
}

.pack-detail.fuera-tolerancia {
  border-left-color: var(--color-warning);
}

.pack-detail h4 {
  font-family: var(--font-ui);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--fg-black);
  margin-bottom: var(--sp-3);
}

.pack-item-row {
  padding: var(--sp-2) 0;
  font-size: 0.82rem;
  border-bottom: 1px solid var(--fg-gray-200);
  display: flex;
  align-items: flex-start;
  gap: var(--sp-2);
  flex-wrap: wrap;
}

.pack-item-row:last-of-type {
  border-bottom: none;
}

.pack-icon {
  font-size: 1.1rem;
  flex-shrink: 0;
}

.pack-item-info {
  flex: 1;
  min-width: 0;
  font-size: 0.82rem;
  line-height: 1.5;
}

.pack-unit-cho {
  font-size: 0.68rem;
  color: var(--color-text-secondary);
}

.pack-orientativo {
  background: var(--fg-green-soft);
  border-left: 3px solid var(--fg-green);
  padding: var(--sp-3) var(--sp-4);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  color: var(--fg-gray-700);
  margin-top: var(--sp-3);
}

.pack-warning {
  color: var(--color-warning);
  font-weight: 600;
  font-size: 0.75rem;
}

/* ── 30. Tech Details Rows ──────────────────── */

.tech-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--sp-2) 0;
  border-bottom: 1px solid var(--fg-gray-200);
  font-size: 0.78rem;
}

.tech-row:last-child {
  border-bottom: none;
}

.tech-label {
  color: var(--color-text-secondary);
  font-weight: 500;
}

.tech-value {
  color: var(--color-text);
  font-weight: 600;
  font-family: var(--font-mono);
  font-size: 0.82rem;
}

.tech-balance {
  margin-top: var(--sp-3);
  padding-top: var(--sp-3);
  border-top: 1px solid var(--fg-gray-200);
}

.tech-balance .tech-label {
  display: block;
  margin-bottom: var(--sp-2);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.tech-balance-bar {
  display: flex;
  width: 100%;
  height: 20px;
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.tech-bar-liquid {
  background: var(--color-info-blue);
  color: var(--fg-white);
  font-size: 0.62rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
}

.tech-bar-solid {
  background: var(--fg-green);
  color: var(--fg-gray-700);
  font-size: 0.62rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
}

.tech-balance-legend {
  display: flex;
  justify-content: space-between;
  margin-top: var(--sp-1);
  font-size: 0.68rem;
  color: var(--color-text-secondary);
}

/* ── 31. Variantes (app.js classes) ──────────── */

.variantes-section {
  margin-top: var(--sp-2);
  font-size: 0.7rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
  width: 100%;
}

.variantes-label {
  font-weight: 500;
  font-size: 0.68rem;
  color: var(--color-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.variante-thumb {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-decoration: none;
  background: var(--fg-green-soft);
  border-radius: var(--radius-sm);
  padding: var(--sp-1);
  width: 68px;
  transition: background var(--transition), transform 0.15s ease;
}

.variante-thumb:hover {
  background: var(--fg-green);
  transform: translateY(-2px);
  text-decoration: none;
}

.variante-name {
  font-size: 0.55rem;
  color: var(--fg-gray-700);
  text-align: center;
  line-height: 1.2;
  word-break: break-word;
}

/* ── 32. Utility Classes ─────────────────────── */

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}


/* ── 33. Section Title ───────────────────────── */

.section-title {
  font-family: var(--font-ui);
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-secondary);
  margin-bottom: var(--sp-3);
}

/* ── 34. Timeline ────────────────────────────── */

.timeline-section {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: var(--sp-4);
  margin-bottom: var(--sp-3);
}

.tl-track {
  position: relative;
  padding-left: 52px;
}

.tl-track::before {
  content: '';
  position: absolute;
  left: 24px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--fg-gray-200);
}

.tl-slot {
  position: relative;
  padding: var(--sp-2) 0;
  min-height: 36px;
  display: flex;
  align-items: flex-start;
}

.tl-slot.tl-hour {
  padding-top: var(--sp-3);
  margin-top: var(--sp-2);
  border-top: 1px dashed var(--fg-gray-200);
}

.tl-time {
  position: absolute;
  left: -52px;
  top: var(--sp-2);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 700;
  color: var(--color-text-secondary);
  width: 40px;
  text-align: right;
}

.tl-dot {
  position: absolute;
  left: -29px;
  top: calc(var(--sp-2) + 4px);
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--fg-gray-300);
  border: 2px solid var(--color-surface);
  z-index: 1;
}

.tl-slot:first-child .tl-dot {
  background: var(--fg-green);
  width: 10px;
  height: 10px;
  left: -30px;
}

.tl-actions {
  display: flex;
  flex-direction: column;
  gap: 2px;
  flex: 1;
}

.tl-action {
  font-size: 0.78rem;
  color: var(--color-text);
  line-height: 1.5;
}

.tl-icon {
  font-size: 0.9rem;
}

.tl-drink {
  color: var(--color-info-blue);
  font-weight: 500;
}

.tl-solid {
  color: var(--fg-green-dark);
  font-weight: 600;
}

.tl-rest {
  color: var(--fg-gray-300);
  font-size: 0.72rem;
}

.tl-summary {
  margin-top: var(--sp-3);
  padding-top: var(--sp-3);
  border-top: 1px solid var(--fg-gray-200);
  font-size: 0.72rem;
  color: var(--color-text-secondary);
  text-align: center;
}

/* ── 35. Form Section Scrollbar (desktop) ──────── */

.form-section {
  scrollbar-width: thin;
  scrollbar-color: var(--fg-gray-300) transparent;
}

.form-section::-webkit-scrollbar {
  width: 4px;
}

.form-section::-webkit-scrollbar-track {
  background: transparent;
}

.form-section::-webkit-scrollbar-thumb {
  background: var(--fg-gray-300);
  border-radius: 4px;
}


/* =================================================
   MEDIA QUERIES — Mobile-first breakpoints
   ================================================= */

/* ── Breakpoint: 640px (small tablets, landscape phones) ── */

@media (min-width: 640px) {
  :root {
    --header-height: 48px;
  }

  .header-title {
    font-size: 0.92rem;
  }

  .header-logo {
    height: 26px;
  }

  /* Wider spacing */
  .form-section {
    padding: var(--sp-6);
    padding-bottom: 80px;
  }

  .results-section {
    padding: var(--sp-6);
  }

  /* Hero metrics can breathe */
  .metric-value {
    font-size: 1.75rem;
  }

  .metric {
    padding: var(--sp-5) var(--sp-4);
  }

  /* Export buttons side by side */
  .export-section {
    flex-direction: row;
  }

  .btn-export {
    flex: 1;
  }
}


/* ── Breakpoint: 768px (tablets, side-by-side layout) ──── */

@media (min-width: 768px) {
  :root {
    --header-height: 52px;
  }

  .header {
    padding: 0 var(--sp-6);
  }

  .header-logo {
    height: 28px;
  }

  .header-title {
    font-size: 1rem;
  }

  /* Side-by-side layout: form left, results right */
  .app-container {
    flex-direction: row;
    align-items: flex-start;
  }

  .form-section {
    width: var(--input-panel-width);
    flex-shrink: 0;
    position: sticky;
    top: var(--header-height);
    height: calc(100vh - var(--header-height));
    overflow-y: auto;
    border-right: 1px solid var(--color-border);
    padding: var(--sp-4);
    padding-bottom: 80px;
    background: var(--color-surface);
  }

  .results-section {
    flex: 1;
    min-width: 0;
    padding: var(--sp-6);
    overflow-y: auto;
  }

  /* Sticky button stays within the form panel */
  .btn-calcular-wrap {
    position: sticky;
    bottom: 0;
    margin: 0 calc(-1 * var(--sp-4));
    padding-left: var(--sp-4);
    padding-right: var(--sp-4);
    background: linear-gradient(to top, var(--color-surface) 60%, transparent);
  }

  /* Hero metrics in a row */
  .hero-metrics {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--sp-4);
  }

  .metric-value {
    font-size: 2rem;
  }

  /* Context selector can be smaller */
  .ctx-btn {
    min-height: 44px;
    font-size: 0.78rem;
  }
}


/* ── Breakpoint: 1024px (desktops, wide layout) ────────── */

@media (min-width: 1024px) {
  :root {
    --header-height: 56px;
    --input-panel-width: 380px;
  }

  .header {
    padding: 0 var(--sp-8);
  }

  .header-logo {
    height: 30px;
  }

  .header-title {
    font-size: 1.05rem;
  }

  /* More generous spacing */
  .form-section {
    padding: var(--sp-5);
    padding-bottom: 80px;
  }

  .results-section {
    padding: var(--sp-8);
  }

  /* Hero metrics breathe more */
  .metric {
    padding: var(--sp-6) var(--sp-5);
  }

  .metric-value {
    font-size: 2.2rem;
  }

  .metric-label {
    font-size: 0.68rem;
  }

  /* Pack card wider */
  .pack-card {
    padding: var(--sp-5);
  }

  /* Carry card wider */
  .carry-card {
    padding: var(--sp-5);
  }

  /* Hydration card wider */
  .hydration-card {
    padding: var(--sp-5);
  }

  /* Button wrap adjusts to wider panel */
  .btn-calcular-wrap {
    margin: 0 calc(-1 * var(--sp-5));
    padding-left: var(--sp-5);
    padding-right: var(--sp-5);
    background: linear-gradient(to top, var(--color-surface) 60%, transparent);
  }
}


/* ── Breakpoint: 1280px (large desktops) ───────────────── */

@media (min-width: 1280px) {
  .app-container {
    max-width: 1400px;
  }

  .hero-metrics {
    gap: var(--sp-5);
  }
}